Process of treating artificial fibers



Patented Mar. 14, 1933 UNITED STATES OFFICE HANS CAESAR STUHLHANN, OF FREHNITZ, GIEHZHANY, ASEIGNOE "1'0 1., G. FWENDT- DUSTBIE AKTIENGESELLSCHAFT, 0F FRANKFOBT-OH-THE-MH, GERMANY PROCESS OF TREzlflJENG ARTH'KCIAL WWW Ho Drawing. Application filed October 05,, 1000,, {Serial 1%. 013,547, and infiermany November 16, 1928.

The present invention relates to a process of treating bunches of artificial fibers in a continuous manner in the course of their manufacture and more particularly to an after-treatment of artificial fiber imnches of high total titer on their way from. the precipitating bath to the collecting device.

According to my invention bunches of artificial fibers of high total titer and astonishingly good physical properties are obtainable in the viscose spinning process by subjecting the freshly produced fibers collected to form a bunch in the acid moist state, that is, when leaving the precipitating bath, to a tension as high as possible, and by passing them simultaneously through a hot water bath before the usual washing operations and after-treatments take place.

My new operation may be performed in the following manner:

A fiber bunch having a total titer of, for instance, 10,000 to 100,000 deniers is formed by collecting the fibers which are produced by a correspondent plurality of spinning nozzles in a viscose spinning process. The freshly produced and consequently acidmoist fiber bunch is passed through a trough having a len th of about 2 to 12 meters, but preferably of 5 meters and being filled with water kept at-a temperature of about 70 to 100 (1, care being taken that the fiber bunch is completely beneath the surface of the hot water. Simultaneously I stretch the fiber by subjecting them to a high tension of, for instance, 0.5 to'0.8 kilograms per square millimeter The speed with which the fiber bunch is guided through the bath may vary between 40 to 60 meters per minute. Obviously, the speed is dependent from the length of the water bath. The stretching of the bunches in the water bath may be performed in any known manner, for instance by causing them to run over rods or rolls so that they form an angle on their way or by (guiding them over a lurality of rollers of i eral velocity.

bunch in a water bath of a fierent and adjusts le periphing a temperature of 70 to 100 (3,, and under the action of the high tension the fiber bunch soaked with the acid liquid of the precipitating bath is very quickly complete ly coagulated. The bunch of fibers then is desulfurized, bleached and finished in the usual manner. Thus very valuable products are obtainable. The single fibers of the bunch have for instance a titer of 1.4 denier-s and a dry tenacity of about 1 grams and a wet tenacity of about 2 grams, while fibers treated in a hot waterbath without tension show a dry tenacity of 2.9 grams and a wet tenacity of 1.2 grams. Furthermore, the material obtained according to my process shows an extremely good luster,

What I claim is:

1. The process which comprises treat' in a continuous manner bunches of artificia fibers obtainable by precipitating a viscose solution in an acid precipitating bath in an acid-moist state with hot water, and simultaneously stretching the fibers.

2. The

ing artificial fibers made from a viscose sola bunch of a total titer of a out $0,000 to 100,000 deniers, and treatin the acid-moist at 70 to 100 (1., and simultaneously stretching the fibers. 3. The recess which comprises collecting artificial bers made from a viscose solution leayin the precipitating bath to fo a bunch o a total titer of about 40,000 to 100,000 deniers, passing the bunch through a water bath of a-length of-about 2 to 12 meters bei lrept at a temperature of about 7 0 to 100 40 to 60' meters r minute, and subj the bunch sim taneously to a tension 0 about 0.5 to 0.8 hlograms r square meter.

ture.

The fiber bunch coming from the pre 0 cipitating bath is not coa lated through? out. Under the action of t e hot liquid havrocess which comprises collectwlth a drawing speed of about u In testimony whereof, afix my signaution leaving the precipitatin bath to form 

